INQUISAL   20936
INSTITUTO DE QUIMICA DE SAN LUIS "DR. ROBERTO ANTONIO OLSINA"
Unidad Ejecutora - UE
artículos
Título:
Cloud point extraction of mercury with PONPE 7.5 prior to its determination in biological samples by ETAAS
Autor/es:
ARANDA, P.R., GIL, R.A., MOYANO, S., DE VITO, I.E., MARTINEZ, L.D.
Revista:
TALANTA
Editorial:
Elsevier
Referencias:
Año: 2008 vol. 75 p. 307 - 311
ISSN:
0039-9140
Resumen:
Cloud point extraction (CPE) has been used for the pre-concentration of mercury, after the formation of a complex with 2-(5-bromo-2-pyridylazo)-5-(diethylamino)-phenol (5-Br-PADAP), and later analysis by electrothermal atomic absorption spectrometry (ETAAS) usingpolyethyleneglycolmono-p-nonyphenylether (PONPE 7.5) as surfactant. The chemical variables affecting the separation step were optimized.Under the optimum conditions, i.e, pH 8.5, cloud point temperature 80 ◦C, 5-Br-PADAP = 4×10−5 mol L−1, PONPE 7.5 = 0.2%, sample volume= 1.0 mL, an enhancement factor of 22-fold was reached. The lower limit of detection (LOD) obtained under the optimal conditions was0.01gL−1. The precision for 10 replicate determinations at 2.0 gL−1 Hg was 4.0% relative standard deviation (R.S.D.). The calibration graphusing the pre-concentration system for mercury was linear with a correlation coefficient of 0.9994 at levels near the detection limits up to at least16gL−1. The method was successfully applied to the determination of mercury in biological samples and in certified reference material (QCMETAL LL3).© 2007 Elsevier B.V. All rights reserved.